Download Heart Rhythm Refresher Course 2014 Module 1: My Diagnostic

Dr Yue Chiu Sun
Consultant and Head
Division of Cardiology
Dept of Medicine & Geriatrics
United Christian Hospital
6 Apr 2014
Case 1
 Mr. WWK age 51
 Non-smoker, non-drinker
 PMH:
 psoriasis
 Mother diagnosed to have HOCM
 family screening previously recommended
Presentation
 Played badminton after work -> sudden collapse
 Bystander CPR started
 Ambulance crew arrived
VF
At AED
 BP 133/92 P 120 bpm
 Given amiodarone infusion
 GCS 3/15
 PERL
 Intubated for ventilatory support
 Consulted CCU-> admitted for further
management
ECG abnormality?
At CCU
Bedside Echo
 Fair echogenicity
 Overall satisfactory LV systolic function
 No apparent RWMA noted
 No LVH noted to suggest HCM or LVOT obstruction
 No pericardial effusion
Seizure
 given sodium valproate 400 mg q8h iv
 Urgent CT brain: no SOL / haemorrhage
What’s next step?
Progress
 Consulted ICU
 Admitted ICU
 Therapeutic hypothermia
sedation (dormicum, morphine) + muscle relaxant (atracurium)
 induction with 2.5L of 4°C ice cold saline
 aimed at body T 32-34°C; maintained with wet blankets
 continued rectal probe monitoring
Inotropic support
NG tube feeding started
ECG : ST↑V2-3 and T V2-4
LDH 301 → 288; CK 395 → 932
TnT 33 → 1169
aspirin 160 mg daily PO started
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During Hypothermia
Progress
 ECG : deep T over V2-6 (probable ACS : Anterior
NSTEMI)
 Echo:
- LV anteroseptal & apical hypokinesia; impaired
LV function
 Re-warming with 0.25 °C per hr
 Reduced inotropic support gradually
 Extubated the next day -> transferred back to CCU
To CCU
 Clopidogrel, Simvastatin, Metoprolol were added
 bedside echo: LVEF 50%, fair LV contraction; RWMA
noted (similar to ICU findings)
 Fully alert, not in heart failure
Coronary angiogram and PCI was performed
 R dominance, LM normal, LAD proximal 80%, mid
LAD 70% stenosis, LCx mild disease, RCA normal
 Stenting to proximal and mid LAD
Uneventful recovery and discharged home
Post-PCI
Anterior STEMI: Therapeutic Hypothermia
and Primary PCI
Post-Cardiac Arrest Care: 2010 American Heart
Association Guidelines for Cardiopulmonary
Resuscitation and Emergency Cardiovascular Care
Recommend that comatose (ie, lack of meaningful response
to verbal commands) adult patients with ROSC after out-ofhospital VF cardiac arrest should be cooled to 32°C to 34°C
(89.6°F to 93.2°F) for 12 to 24 hours (Class I, LOE B)
Induced hypothermia also may be considered for comatose adult patients with
ROSC after in-hospital cardiac arrest of any initial rhythm or after out-of-hospital
cardiac arrest with an initial rhythm of pulseless electric
activity or asystole (Class IIb, LOE B)
Circulation. 2010;122:S768-S786
Post–cardiac arrest care algorithm
Peberdy M A et al. Circulation. 2010;122:S768-S786
Copyright © American Heart Association, Inc. All rights reserved.
Case 2
Mr WWM age 52
History of idiopathic DCMP (CTCA-> normal coronary
arteries) and AF
Admitted for post-VT/VF arrest after being found
collapse in street (pulseless VT/VF with prolonged
resuscitation > 1 hr and repeated defibrillation);
intubated for mechanical ventilation
VT after admission
Progress
 Acute renal and liver failure requiring temporary HD
support
 Progressive improvement and extubated later
 Echo: poor LV function EF ~20% with global
hypokinesia
 Coronary angiogram: mild CAD only
 ICD was implanted
 Transfer to convalescence hospital for rehabilitation,
good neurological recovery
Diagnostic Approach to SCD survivor
1. Clinical History
eg. known IHD/congenital heart disease or past
history of MI, CV risk profile, triggering factors
(exercise, stress – eg. ACS, WPW, HCM, AS,
CPVT )
2. Family history of hereditary cardiac arrhythmia or
congenital heart disease, FH of SCD
3. Transient and reversible causes
4. Evaluation for structural heart disease
5. Evaluation for those without structural heart disease
Clinical History and Baseline Investigation
Transient or reversible causes
 Evidence of ACS esp. STEMI
 Drug history: anti-arrhythmic drugs, psychiatric
drugs, OTC drugs, herbal medicine, drug abuse
 Medications esp. those ↑ QTc
 Electrolyte and acid-base abnormalities:
hypokalemia K, hyperkalemia ↑K, Ca, acidosis
Investigations for SCD survivor
1. ECG
- Myocardial ischemia or infarction (? ST
elevation in V1 & aVR)
- myocarditis (eg. T wave inversion, ST segment
elevation or depression, heart block, ↑QT
interval)
- high grade AV block
- Brugada Syndrome (polymorphic VT/VF)
- Long QT or short QT
- Wolf-Parkinson-White WPW syndrome esp.
preexcited AF
- CPVT, Early repolarization syndrome (ERS)
ECG
 PR: short PR (WPW with preexcitation)
 Q wave: MI
 QRS: delta wave, BBB
 QT : congenital long QT, acquired
 QT : short QT
 ST : STEMI, myocarditis, Brugada syndrome
 ST  : myocardial ischemia, NSTEMI, myocarditis
 T : tall T wave in K, hyperacute phase in AMI
 T : myocardial ischemia, NSTEMI, epsilon wave (ARVC)
 P and QRS relationship: high grade AV block
 J point elevation
ECG diagnosis?
Brugada ECG
Brugada ECG
Brugada syndrome: polymorphic VT/VF
WPW with preexcited AF
Early repolarization syndrome ERS
ERS is defined as an elevation of the J point (the junction between the end of the QRS complex
and the beginning of the ST segment) and/or ST segment by at least 0.1 mV from baseline
Early repolarization syndrome ERS
ERS can be divided into three subtypes:
Type 1 - which is predominantly characterized by an ERP that is detected with
lateral precordial leads, is prevalent among healthy male athletes and rarely seen
in VF survivors
Type 2 - which is predominantly detected through the inferior or inferolateral
leads, is associated with a higher level of arrhythmia risk than type 1 ERS
Type 3 - which involves ERPs that are observed globally through the inferior,
lateral, and right precordial leads, is associated with the highest level of risk for
malignant arrhythmias and often associated with VF storms
Early repolarization syndrome ERS
 early repolarization in the inferior ECG leads has been
associated with idiopathic VF and has been termed as
ERS
 ERS has emerged as a marker of risk for idiopathic VF
and sudden death. However, the incidental discovery
of a J wave on routine screening should not be
interpreted as a marker of “high risk” for sudden death
Catecholaminergic Polymorphic VT (CPVT)
Affected patients typically present with life-threatening VT or VF occurring during emotional or
physical stress, with syncope often being the first manifestation of the disease. Although sporadic
cases occur, this is a largely familial disease . The majority of known cases are due to mutations in
the cardiac ryanodine receptor, which is the cardiac sarcoplasmic calcium release channel
VT morphology may vary continuously, from beat to beat, or may appear as a bidirectional VT
Congenital Long QT syndrome LQTS
With 4 or more points the probability is high for LQTS, and with 1 point or less the
probability is low. Two or 3 points indicates intermediate probability.
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QTc (Defined as QT interval / square root of RR interval)
o >= 480 msec - 3 points
o 460-470 msec - 2 points
o 450 msec and male gender - 1 point
Torsades de Pointes ventricular tachycardia - 2 points
T wave alternans - 1 point
Notched T wave in at least 3 leads - 1 point
Low heart rate for age (children) - 0.5 points
Syncope (one cannot receive points both for syncope and Torsades de pointes)
o With stress - 2 points
o Without stress - 1 point
Congenital deafness - 0.5 points
Family history (the same family member cannot be counted for LQTS and sudden
death)
o Other family members with definite LQTS - 1 point
o Sudden death in immediate family (members before the age 30) - 0.5
points
Long QT1
Congenital Long QT syndrome
Syndrome
Frequency
Locus
Protein
(Functional Effect)
KCNQ1 (LQT1)
RWS, JLNS
40–55
11p15.5
Kv7.1 (↓)
KCNH2 (LQT2)
RWS
30–45
7q35–36
Kv11.1 (↓)
SCN5A (LQT3)
RWS
5–10
3p21–p24
NaV1.5 (↑)
ANKB (LQT4)
RWS
<1%
4q25–q27
Ankyrin B (↓)
KCNE1 (LQT5)
RWS, JLNS
<1%
21q22.1
MinK (↓)
KCNE2 (LQT6)
RWS
<1%
21q22.1
MiRP1 (↓)
KCNJ2 (LQT7)
AS
<1%
17q23
Kir2.1 (↓)
CACNA1C (LQT8)
TS
<1%
12p13.3
L-type calcium
channel (↑)
CAV3 (LQT9)
RWS
<1%
3p25
Caveolin 3 (↓)
SCN4B (LQT10)
RWS
<1%
11q23.3
Sodium channel-β4
(↓)
AKAP9 (LQT11)
RWS
<1%
7q21–q22
Yotiao (↓)
SNTA1 (LQT12)
RWS
<1%
20q11.2
Syntrophin α1 (↓)
KCNJ5 (LQT13)
RWS
<1%
11q24
Kir3.4 (↓)
Gene
Short QT
syndrome
Genetic basis of SQTS
QTc (msec)
Locus
Gene (cardiac ion
channel)
SQT 1
286 ± 6
11p15
KCNH2 (IKr) ↑
SQT 2
302
7q35
KCNQ1 (IKs) ↑
SQT 3
315-330
17q23
KCNJ2 (IK1) ↑
SQT 4
331-370
10p12
CACNB2b (ICa) ↓
SQT 5
346-360
12p13
CACNA1C (ICa) ↓
SQT 6
330
7q21-22
CACNA2D1 (ICa) ↓
Investigations for SCD survivor
2. Blood tests
eg. RFT, ABG, cardiac biomarkers, Ca, Mg, drug
level (digoxin, TCA etc.), toxicology screen
Investigations for SCD survivor
3. Echocardiogram
- LV function and EF, RWMA, heart chamber size
- significant valvular disease eg. aortic stenosis
- cardiomyopathy eg. DCM, HCM/HOCM, ARVC
Investigations for SCD survivor
4. Coronary angiography and cardiac
catheterization
- r/o significant coronary artery disease,
anomalous coronary arteries (? coronary artery
course between aorta & pulmonary trunk),
congenital heart disease
5. CT scan
- aortic dissestion, coronary anomaly, congenital
heart disease
6. Cardiac MRI
- structural heart disease eg. HCM, ARVC, LV
non-compaction
Investigations for SCD survivor
7. EP study (limited role : post-cardiac arrest)
- exclude other arrhythmias, ablative therapy
(?WPW, VT foci)
8. Genetic testing, family screening and counselling
eg. long QT, HCM, Brugada syndrome, CPVT
- commercially available genetic testing exists for
HCM, DCM, ARVC, LV non-compaction, LQTS,
SQTS, CPVT, and BrS
Genetic Testing for Potentially Lethal,
Highly Treatable Inherited
Cardiomyopathies/Channelopathies in
Clinical Practice
David J. Tester and Michael J. Ackerman
Circulation. 2011;123:1021-1037
Indications for genetic testing. Provided is a table of possible indications for genetic
testing for hypertrophic cardiomyopathy (HCM), long-QT syndrome (LQTS),
catecholaminergic polymorphic ventricular tachycardia (CPVT), and Brugada syndrome
(BrS). LVH indicates left ventricular hypertrophy; QTc, corrected QT interval; TdP,
torsade de pointes; Neg., negative; and SUD, sudden unexplained death. The plus symbol
( ) represents a positive indication for genetic testing; the negative symbol ( )
represents an indicator that does not warrant genetic testing for the specific disorder;
and the / symbol represents an indicator that may or may not warrant genetic testing.
Utility of genetic testing. Shown is the current diagnostic, prognostic, and
therapeutic utility of genetic testing for hypertrophic cardiomyopathy (HCM),
long-QT syndrome (LQTS), catecholaminergic polymorphic ventricular
tachycardia (CPVT), and Brugada syndrome (BrS). The plus symbol ( )
indicates the test has utility, the negative symbol ( ) indicates no current
measurable utility, and the / symbol indicates the test may have some utility